I also like volume releases, but those are special for Christmas, scans group anniversary etc, so it must take a lot of work...

I voted for set releases, because if it is a series I really like, I get all "omg, twooo new chapters!!", so it always make me more happy. I don't mind chapter releases either, but I tend to wait for more releases to read it (actually, if it is one volume long, I wait until it is completely scanlated, because I'm really curious... it is funny to see the process of translation happening with the year passing).